प्रकाश - परावर्तन तथा अपवर्तन | CLASS 10 - विज्ञान | 7 AM Class by Ruchi Katiyaar Ma'am | L15

12 PM Special Class | Class 11 - STRUCTURE OF ATOM || BOHR MODEL By Yakshu Ma'am

Thirty children were asked about the number of hours they watched TV programmes in the previous week. The results were found as follows: 1 6 2 3 5 12 5 8 4 8 10 3 4 12 2 8 15 1 17 6 3 2 8 5 9 6 8 7 14 12 (i) Make a grouped frequency distribution table for this data, taking class width 5 and one of the class intervals as 5 - 10. (ii) How many children watched television for 15 or more hours a week?

For a decomposition, the values of rate constants at two different temperature are given below: k_(1) = 2.15 xx 10^(-8)L mol^(-1)s^(-1) at 650 K k_(2) = 2.39 xx 10^(-7) L mol^(-1)s^(-1) at 700 K Calculate the value of activation energy for the reaction (R= 8.314 JK^(-1) mol^(-1))

Following table shows the marks scored by a group of 90 students in a mathematics test of 100 marks. Marks 0-20 20-30 30-40 40-50 50-60 60-70 70-100 No. of Students: 7 10 10 20 20 15 8 Find the probability that marks scored by a student in the class is: at most 60 marks (ii) at least 60 marks (iii)not more than 50 marks

Consider the marks, out of 100, obtained by 51 students of a class in a test, given in Table 14.9. M a r k s"N u m b e r o f S t u d e n t s"0-10 5 10-20 10 20-30 4 30-40 6 40-50 7 50-60 3 60-70 2 70-80 2 80-90 3 90-100 9Tot a l 51 Draw a freque

PARAGRAPH A There are five students S_1, S_2, S_3, S_4 and S_5 in a music class and for them there are five seats R_1, R_2, R_3, R_4 and R_5 arranged in a row, where initially the seat R_i is allotted to the student S_i , i=1, 2, 3, 4, 5 . But, on the examination day, the five students are randomly allotted five seats. For i=1, 2, 3, 4, let T_i denote the event that the students S_i and S_(i+1) do NOT sit adjacent to each other on the day of the examination. Then, the probability of the event T_1nnT_2nnT_3nnT_4 is 1/(15) (b) 1/(10) (c) 7/(60) (d) 1/5

The marks obtained (out of 20) by 30 students of a class in a test are as follows: 14, 16, 15, 11, 15, 14, 13, 16, 8, 10, 7, 11, 18, 15, 14, 19, 20, 7, 10, 13, 12, 14, 15, 13, 16, 17, 14, 11, 10, 20. Prepare a frequency distribution table for the above data using class intervals of equal width in which one class interval is 4-8 (excluding 8 and including 4).

the daily minimum temperatures in degrees Celsius recorded in a certain Arctic region are as follows: -12. 5 ,-10. 8 ,-18. 6 ,-8. 4 ,-10. 8 ,-4. 2 ,-4. 8 ,-6. 7 ,-13. 2 , -11. 8 ,-2. 3 , 1.2 , 2.6 ,0,-2. 4 ,0, 3.2 , 2.7 , 3.4 ,0,-2. 4 ,-2. 4 ,0, 3. 2 , 2.7 , 3.4 ,0,-2. 4 ,-5. 8 ,-8. 9 ,-14 ,6,-12. 3 ,-11. 5 ,-7. 8 ,-2. 9 Represent them as frequency distribution table taking -19. 9\ to-15 as the first class interval.

CH. 14 STATISTICS Q1 Class 0-8 8-16 16-24 24-32 32-40 Frequency 10 12 26 9 15 e mean of above data by: () Direct method () Assumed mean method (ii) Step deviati iop metod. Q2 The following distribution shows the daily pocket allowance of children of a locali ty. The mean pocket allowance is Rs 20. Find the missing frequency Daily Pocket 0-20 20-40 40-60 0-80 80-100 No. Of Children 7 10 9 13 Q3. The following table shows age distribution of persons in a particular region. Find the: (0) mean age (i)modal age (ili) median age Age? Below!0 Below20 Below30 Below 40, Below 50 Belo No, persons ? 250 190 100 40 15 4 Arithmetic mean of the following frequency distribution is 50. Find the missing frequencies C.I. ? 0-20 20-40 40-60 60-80 80-100 Tota